(based on A. I. Vdovin, Soloviev Vadim Georgievich (1925-1998), Physics of Particle and Nuclei, Vol. 30, No. 4, 2000)
Vadim Georgievich Soloviev was born in 1925 on October 12, in Kazan. His parents (father, Georgii Georgievich Soloviev and mother, Lidiya Pavlovna Solovieva) were physicians.
In January 1943, when Vadim was a student in the last grade of a secondary school, he was summoned to the Red Army. He was trained at the military school and then was on acting service. Prior going to army Vadim managed to pass the exams to obtain the school-leaving certificate, which secured him admittance to the Physics Department of Leningrad University right after demobilization in October 1945.
Soloviev became a student of the course where students were prepared to be specialists at the factories and institutes of the developing Soviet atomic project. After successfully graduating from the university in December 1950, he started working at the Hydraulic Engineering Laboratory in Dubna.
Soloviev started working in the sector of theoretical physics, aimed basically at the study of elementary particle physics, and this became the object of his early research. However, the results obtained by Soloviev at that time were published only as classified reports. They became accessible only several years later (in 1954-1955).
In 1953, Soloviev met N.N. Bogoliubov and started to attend his seminars at the Physics Department of Moscow State University and at the Steklov Mathematical Institute and worked under Bogoliubov's supervision. For a certain period, Soloviev's scientific interest was quantum field theory, and in 1956, he defended the Ph.D. thesis on the theme "Construction of the Approximate Green's Functions in the Pseudoscalar Meson Theory" at Moscow State University.
In March 1956, the Joint Institute for Nuclear Research was founded in Dubna. The first director of JINR was D. I. Blokhintsev, who initiated the creation of the Laboratory of Theoretical Physics (LTP). Soloviev actively participated in the foundation of the Laboratory and became one of its first collaborators together with many other students of Bogoliubov.
As a postdoctoral researcher Soloviev was attracted by the problem of parity conservation in strong and electromagnetic interactions. He suggested that the conservation of spatial parity is connected with the gauge invariance of the interaction. Soloviev eagerly defended this idea which brought about a very passionate discussion.
At the same time, Soloviev took interest in the problem of superfluidity of nuclear matter and a possible role of pairing correlations of the superconducting type in atomic nuclei. It all happened under the influence of Bogoliubov and his works on the microscopic theory of superconductivity. The problem of pairing correlations of the superconducting type in atomic nuclei was a topical one and attracted the attention of many scientists. The first Soloviev's research paper in this field entitled "On the Interaction of Nucleons Resulting in the Superfluid State of the Atomic Nucleus" (Zh. Eksp. Teor. Fiz., 1958, vol. 35, p. 823) made him one of the leading theoreticians of nuclear physics.
In 1958-1962, Soloviev developed the theory of pairing correlations of the superconducting type in atomic nuclei. Conditions under which the Cooper pairing in nuclei occurs were investigated, the blocking effect (the influence of unpaired particles on the pairing characteristics of the whole system) was predicted, as well as the existence of multiquasiparticle excited states of nuclei. Vadim Georgievich first studied the way pairing correlations influence the probabilities of nuclear beta- and gamma-decays and discovered that they are the main phenomena that cause the acceleration of alpha-transitions between the ground states of even-even nuclei.
These investigations, part of which he conducted in Copenhagen at the Niels Bohr Institute, brought him international recognition. In 1962, Vadim Georgievich defended doctoral dissertation on the subject "Pairing Correlations of the Superconducting Type in Atomic Nuclei." It became the basis of his first book The Influence of Pairing Correlations on the Properties of Atomic Nuclei , published in 1963. The same year, Soloviev received was awarded the JINR prize for his research work on nuclear theory.
In 1963, a group of scientists who worked on various theoretical problems of nuclear physics formed the Department of low and intermediate energy physics at the Laboratory of Theoretical Physics. Vadim Georgievich became the head of this department and, at the same time, Vice-Director of the Laboratory of Theoretical Physics.
In the mid-1960s, Soloviev concentrated totally on problems of nuclear theory. Methods of the many-body theory and the Bogoliubov method of self-consistent field, in particular, appeared to be very effective in constructing new microscopic models of the structure of heavy nuclei. Soloviev applied these methods to explain the properties of vibrational excitations of deformed nuclei and their connection with quasiparticle ones. Together with the development of new fundamental methods that were used to describe nuclear excitations, Soloviev started to calculate and analyze the properties of specific nuclei. He and his collaborators carried out vast investigations of spectra of low-lying nonrotational states of deformed nuclei. Those studies were performed in close contact with the experimenters from Dubna and Leningrad and strongly influenced the development of nuclear spectroscopy. The structure of quadrupole and octupole oscillations of deformed nuclei was investigated for the first time. It was predicted that there existed deformed nuclei with the mass numbers A ~ 100. This was confirmed by experiments in 1970. The hypothesis about the possible difference of the equilibrium deformations of the ground and excited states of the nuclei was put forward.
In 1971, a fundamental monograph by Soloviev was published by "Nauka" under the title Theory of Complex Nuclei (within 5 years, it was translated into English and published by Pergamon).
Vadim Georgievich was an expert in spectroscopy of deformed atomic nuclei. It seemed sometimes to his collaborators that he knew by heart the energies and decay parameters of tens and hundreds of states. Soloviev could easily describe the nature of one or another state and estimate the reliability of new data, comparing those of various experiments and theoretical calculations. He followed very systematically the experimental successes reported in the literature and kept in touch directly with experimental groups. This trait made his works well known to experimenters and his results were often used when experimental data had to be analyzed and interpreted. The book The Structure of Even Deformed Nuclei, Moscow: Nauka, 1974, written together with E. P. Grigoriev from Leningrad State University, is a good example of the collaboration of Soloviev with experimenters. In 1976, the first prize of JINR went to Soloviev with his collaborators for their studies of the theory of excitations of deformed nuclei.
In the early 1970s, studies of nuclear structure shifted from low-excited states to high energies of excitations up to the energy of stripping of a nucleon and higher, i.e., up to 20-30 MeV. Traditionally, statistical approaches were used to describe the nuclear properties at such energies. As one of the first, Soloviev started to develop the microscopic approach that had to explain the nonstatistical effects observed in many cases. As a first step, when analyzing and explaining correlations between different characteristics of highly excited states, he proposed to use the model wave function represented as a sum of components with an increasing number of quasiparticles. Soloviev noticed that the greatest part of available experimental data on such excitations was connected with the very simple components of that wave function. To understand the spectra of nuclei, one has to learn to calculate the distribution of these components over nuclear levels. Even using very general assumptions Soloviev succeeded in obtaining some interesting qualitative results. However, using this approach, it appeared to be too difficult to explain the special properties of nuclear spectra. Working on the practical incarnation of his idea, Soloviev formulated the quasiparticle-phonon nuclear model of a nucleus (QPNM). In this model, not only quasiparticles but also phonons are considered as elementary blocks when constructing the model wave function. By this approach, phonons, correlated superpositions of two-quasiparticle states, are considered as bosons in the first approximation, and this makes the task much easier. The idea appeared to be very fruitful.
With the help of QPNM, Soloviev and his collaborators investigated and explained a wide range of the properties of nuclear excitations. What they achieved first was that they estimated the contribution of the collective motions of a nucleus to the density of nuclear states at the binding energy of a nucleon. After that, they succeeded in calculating (for the first time within the framework of the microscopic theory) neutron and radiation strength functions and explaining why there are substructures at the low-energy tail of the dipole photoabsorption, etc. The first quantitative calculation of the widths of the giant resonances in heavy nuclei was a very big success for the group. It was shown, in particular, that the mechanisms of the formation of those widths are different in spherical and deformed nuclei. This series of research papers won the JINR first prize in 1979.
The QPNM appeared to be a very flexible model; its formalism has been developed and improved by Soloviev and his group for many years. In the 1980s, a consistent procedure was developed that allowed one to consider the corrections related to the fermion structure of phonons. The resonance-like structures connected with the excitation in the reactions of the nucleon transfer of high-lying one- or two-quasiparticle states were systematically studied, as well as the spin and charge-exchange giant resonances.
The QPNM appeared at the point when the development of nuclear physics experiments made it possible to obtain detailed information about nuclear excitations with energies of 2-4 MeV. With its help, some very fine properties of the two-phonon states of spherical nuclei were explained. Vadim Georgievich studied very thoroughly the problem whether there existed two-phonon states of deformed nuclei or not, as well as the structure and properties of dipole electric and magnetic excitations. For the development of the quasiparticle-phonon model and explanation of the new experimental data on excitations of deformed nuclei, Soloviev and his group received the first prize of JINR in 1995.
Scientific studies and research were the most important matters of life for Soloviev. However, science does not live by itself; it is connected with the life of human society and is free from neither good nor bad influences of the latter. As Vadim Georgievich was always an active citizen and a very energetic one, he was anxious about the destiny of science, its internal life, and its position in society. As a student, according to his own words, he "fought against all those who tried to forbid quantum mechanics on the basis of pseudo-philosophical conceptions." Later on, as a scientist, he spent a lot of time and effort to organize and develop research in nuclear physics.
It was already mentioned how decisive his role was in the creation of the Department of the Nuclear Theory at LTP. As the founder of the Department of low and intermediate energy physics Vadim Georgievich took care of investigations not only in nuclear structure but also in few-body systems, theory of reactions (including reactions with heavy ions), and the theory of interactions with nuclei at high energies. He oriented himself and directed others to support JINR experiments. This was one of the most important tasks of the Department and he used to emphasize it. This support was carried out in relation to the Laboratory of Nuclear Problems (V. G. Soloviev, R. A. Eramzhyan, V. B. Belyaev ), Laboratory of Neutron Physics (L. A. Malov et al.), Laboratory of Nuclear Reactions (V. V. Pashkevich, V. K. Lukyanov, R. V. Jolos, et al.), and the Laboratory of High Energies (V. S. Barashenkov, V. D. Toneev, et al.) with active participation then and now of collaborators from JINR Member States.
Thanks to the great organizing capabilities of Soloviev, the Department successfully developed and multiplied the subjects of investigations, reacting accordingly when new directions in nuclear physics arose. We must mention the very democratic way of the internal life of the Department. For instance, new employees were admitted only after the collective discussion of a every competing candidate. For many years, the general meetings of the Department were held annually, where every collaborator had to report on the results obtained and everyday needs were discussed. When the staff of the department increased, the reports of every collaborator became impossible because of the lack of time, and only the heads of the groups came out with general reports. It is obvious that the Soloviev's Department played a great role in the development of investigations in theoretical nuclear physics in the JINR Member States. Many actively working theoreticians of the present time started their scientific careers in this Department.
Soloviev founded the scientific school of theoretical nuclear physics in Dubna. He taught and worked a lot with young physicists, being a role model to them. Already in 1961, he had started to give lectures on the modern methods in nuclear theory to the students of the Department of Physics of Moscow State University who visited Dubna. These lectures, later changed and modified in accordance with the new achievements of nuclear theory, became the basis of his monographs: The Theory of Complex Nuclei and the other two written later on, The Theory of the Atomic Nucleus: Nuclear Models, Moscow: Energoizdat, 1981 and The Theory of the Atomic Nucleus: Ouasiparticles and Phonons, Moscow: Energoatomizdat, 1989; Institute of Physics, Bristol and Philadelphia, 1992. For more than 15 years, he was a professor and Deputy Head of the chair of the theory of atomic nucleus of the Department of Physics of Moscow State University. Later (up to 1991), he worked as a professor at the chair of quantum statistics of the same Department. His numerous students successfully work nowadays at institutes and universities of Russia, Bulgaria, Mongolia, Vietnam, and other countries.
For many years, Soloviev was a member of the Scientific Council of the International Center of Theoretical Physics in Trieste, a member of the Council on Nuclear Physics of the European Physics Society, the assistant chairman of the Expert Council of the Higher Certifying Commission of the USSR, served on the Bureau of the Scientific Council of Physics of the Atomic Nucleus of the Russian Academy of Sciences, Scientific-Technical Council of JINR, was a permanent member of the Scientific-Technical Council of LTP, and a member of various specialized councils. On his initiative and under his guidance, international conferences and schools on selected problems of the nuclear structure were held in Dubna and Alushta. Soloviev was a member of the Editorial Boards of the journals Nuclear Physics and Theoretical and Mathematical Physics. His role in the formation and further work of the journal Physics of Elementary Particles and Atomic Nucleus has to be specially mentioned. He was assistant editor-in-chief of this journal from the very beginning of its foundation in 1970.
The scientific merits of Soloviev and his scientific authority were acknowledged by the Russian and international scientific societies. He was awarded the honorary title "Meritorious Scientist of the RSFSR." Soloviev received the Great Silver Medal "For Service to Science and Society" from the Czechoslovakian Academy of Sciences. He was decorated with orders and medals of the JINR Member States.
In his private life, Vadim Georgievich was a kind and sociable man. There always was a place in his life for science, administrative and social cares, sports, and art. He played tennis; was fond of skiing; and very often at the end of the winter, he took short holidays especially to make ski tours in the Dubna area.
Vadim Georgievich was also interested in the philosophy and history of science, and he liked music very much. Very few people knew that, in his childhood, he successfully learned to play the piano. A reminder of this might be the music notes with Rahmaninov's autograph, which was presented to Vadim by his music teacher, who was a student of Rahmaninov. But after choosing science as the matter of his life Vadim Georgievich entirely devoted himself to it.